Answer
A) 1
B) 3.8
Work Step by Step
a) qc = [R]/[Q] = 50/50 = 1
since, qc < Kc so, reaction will move in forward direction to generate more R.
b) Q R
50 50 intial
50-x 50+x at equlibrium
Kc = [R]/[Q]
25 (50+x)/(50-x)
1250 - 25x = 50+x
1200 = 26x
x = 46.2
so, at equlibrium [R] = 50 + X = 50 + 46.2 = 96.2 × 10^-6 M
[Q] = 50 - X = 50 - 46.2
= 3.8 × 10^-6 M